Automatic fuel regulator



c. L. STOKES AUTOMATIC FUEL REGULATOR Dec. 11, 1928.

Filed Mgrch 22, 19 25 5 Sheets-Sheet 1 '3 Sheets-Sheet 2 C. L. STOKES AUTOMATIC FUEL REGULATOR Flled March 22, 1923 Dec. 11, 1928.

Dec. 11,- 1928.

C. L. STOKES AUTOMATIC FUEL REGULATOR Filed March 22, 1923 3 Sheets-Sheet 'fg. S 7

IN VENTOR.

Patented Dec. 11, 1928..

. airs STATES PATENT cue-urns" LAWRENCE sroKEs, or LOS ANGELES, CALIFORNIA, ASSIGNQR 'ro CURTIS B. CAMP, TRUSTEE, or GLENCOE, ILLINOIS. 1 i I AUTOMATIC FUEL REGULATOR.

Application filed March 22, 1923. Serial No. 626,990.

My invention. relates to improvements in automatic priming" and carburetting devices for internal combustion engines.

The principal object-of my invention is to provide means for automatically feeding a preliminary rich charge in order to start an internal combustion engine, and thereafter automatically reducing the'richncss of the charge.

I am enabled todo this by utilizing the heat of the engine itself for the purpose of actuat Ling suitable heat responsive mechanism.

The ordinary means of primingan engine for starting. generally consists of what is known as a choke whereby, by cutting oil the supply of air to thecarburetor, a quantity of raw gasoline is drawn into the engine by its suction. Various other devices are in use 'for the same purpose, but in many cases the engine becomes flooded by an overly rich mixture and will not therefore start, and in other cases the mixture is tom lean and the engine will not start. I V By my invention I am enabled to provide a rich mixture for starting an engine, and thereafter as soon as the charge is fired, 1 am enabled'to automatically cut off the overly rich mixture for starting and thereafter feed a less rich mixture for running the engine until an operative temperature is attained whereby the engine will function Withoutexcess fuel for that temperature. 7

This is principally accomplished by supplying a very 'rich mixture and suddenly cut-" ting this very rich mixture down to a rich nnxture and from thence reducing the richness to normal strength as the engine warms Rcferriug to the drawings in which like numbers indicate the same parts, Fig. 1 is-a view of my invention attached to an internal combustion engine. Fig.2 is a vertical sectional view of part of the apparatus in Fig. 1. Fig. 3 is a vertical sectional view of another part of the apparatus in Fig. 1. Fig. 3f is an alternative of Fig. 3. Fig. 4. is a view showing a second adaptation of my invention attached to an internal combustion engine. Fig. 5 is a part vertical sectionalview of Fig. 4. Fig. 5 is a longitudinal section along the lines 55 of Fig. 5. Fig. 6 is a longitudinal section and viewof part of Fig. 5. Fig. 7 is a part vertical section and view of another adaptation of my invention. Fig. 8 is a longitudinal part section and view along the lines 8--8 of Fig. 7. Fig. 9 is a sectional view along the lines 9 9 of Fig. 7. Fig. 10 is a longitudinal sectional. view along the lines 10- -10 of Fig. 7. i In the preferred embodiment of my inventlon', as shown in Figs. 4 to 10, 1 is an internal combustion engine having an exhaust pipe 2, an inlet manifold 3 to which is attached a carburetor 41, the carburetor beingcontrolled by the usual throttle valve 5. A vacuum tank 6 is attached to 1 for the purpose of feeding liquid fuel to 4 by gravity through a pipe 17, the liquid fuel being drawn from a lower level through a pipe 16 by means of the engine suction which is applied through the vacuum tank from 3 through 7 and 18 is a pipe for circulating cooling water, or it may be part of the water jacket surrounding the engine cylinders. i The vacuum tank is of well-known con struction, such as is known as the Stewart Warner vacuum tank, and this construction need not 'bedescribed" beyond the statement that it contains an inner suction chamber 19 and a liquid reservoir 20, the, reservoir 20 being continuously open to atmosphere through a vent 21.

Inserted in the exhaust pipe 2 is an air bulb 13, connected by a pipe 14 to a Bourdon tube 9 held firmlyin a casing 8, and connected with 14. is a pipe 14 joined to an air bulb 12 inserted in 18 (see Fig. 4).

' The end of 9 is pivotally connected with a rack 10, the rack being supported by guido rods 11,'whic'h engages a pinion 12. 10 may alternatively be held in mesh with 12 by a spring in place of 11. 12 is firmly joined to the top of a hollow rotarylvalve .22 and valve 22 is machined to snugly fit inside the upper part of fitting 23, the lower part of:-23 being threaded unto the upper end of a supply pipe '24 which dips down below the liquid level A.A in reservoir 20 and which is held there in in position by a lock nut 25. L

The lower part of 22 terminates in a pivot point which rests on a stop 26 having perforations 27 therein. Through the pivot point are passages 28 connected to a jet 29 which is adapted to turn with 22 and to always face an 0riice 30 for passing liquid fuel from 20 into i to register, at varied degrees of rotation, with a. port 32 placed in 23 for the purpose of- In another part of 22is a port 31 adapted with the liquid fuel through 30 and thereby vary the proportion of li uid fuel and air which shall be fed through l to the engine.

An enlargement 33 is inserted in 7 and contains a resistance coil 34 which is supplied by current through wires 35 for the purpose of initially vaporizing gasoline fed through 7. The application of current through 35 may be governed by an automatic thermostatic control, such as later described in Fig. 1 or in any well-known manner.

' In the adaptation of my invention to carburetting apparatus, as shown in Fig. 7, I may use similar instrumentalities as already described but arranged in a different manner, wherein the air bulb 13 is placed in the water jacket 18 of engine 1 and 13 is connected by 14 in a similar manner to a Bourdon tube 9. In this particular case tube 9 is pivotally connected with rack 10 meshed with gear 12 which is firmly connected to the upper part of a hollow rotary valve 36,36 being machined to snugly fit inside of a supply pipe 37, the lower part of which dips below the normal liquid level in the float chamber 37 of carburetor 4. Below the liquid level in 37*, a port 38 is placed in the supply pipe 37 and a slit 39 is arranged in 36 to register with 38 thereby permitting a varying amount of liquid fuel to pass into 36 depending on the rotation thereof.

Suction is applied from 3 to the interior of 36 through passages 40, 41 and 42. 41 is so arranged in rotary valve 36 that the rotation 7 thereof will always leave an opening from 40 into 7, and 7 is connected by a pipe 43 to the reservoir 20 and by an extension pipe 15 to the suction chamber 19 in order to continuouslv remove the vapors oflight fractions from the liquid fuel in 6.

8 is securely closed by a cover 44- and vacuum is applied from 40 to the interior of 9 through a connecting pipe 45, the mouth of which is restricted to a small orifice 4O for controlling the rate of evacuating 8. The area of 40 may also be restricted to a small orifice as shown in Fig. 9, for governing the volume of air and gasoline to be supplied to 3.

In the priming of internal combustion engines for starting purposes, it is necessary, depending on the temperature of the engine. to first provide a very rich proportion of gasoline to air if the temperature of the en gine is very low and thereafter as soon as the very rich mixture is fired in the engine, to reduce the richness of the mixture to a rich mixture until the temperature of the engine reaches a point at which a normal mixture can be supplied to and burned by the same. The priming charges are therefore dependent upon the temperature of the engine itself, irrespective of atmospheric temperature, although at times atmospheric temperature corresponds with the engine temperature.

To obtain the steps described automatically, I will describe the operation of the preferred form of my invention as shown in Figs. 4 to .10 inclusive, referring particularly to Figs. 4, 5, and-6.

In starting an internal combustion engine, the throttle 5 is usually kept closed, thereby producing a high degree of vacuum, about 221/ inches of mercury, in manifold 3. Therefore, when en e 1 is cranked, the vacuum in 3 is transmitted through 7 to the interior of 22 through port 30. On starting the engine, the position of ports 30, 31 and 32 are approximately relatively shown in Fig. 5*, wherein 30 is wide open to 7 but 31 is almost closed with respect to 32. Therefore the suction acting through 30 will cause a practically solid stream ofgasoline to. be drawn from 20 through 24, 27, 28 and 29.-

This excessively rich mixture of gasoline and air will be passed into the engine whereit is ignited and the exhaust gases are discharged through 2 to atmosphere. At the first explosion the heat of theexhaust gases is applied to 13 thereby causing an expansion of the air in the same, it being understood that 13, 13 14, 14 and 9 form a closed system containing a fluid, which in the present instance is air. v

The pressure of the heated air in 13 acting through 14 on the Bourdon tube 9 causes 9 to expand, whereby rack 10 actuates 12 to partially rotate valve 22, thereby reducing the flow of gasoline through 29, because 31 then admits more air through 32 to partially break the suction supplied .to 29 through 30 for drawing gasoline therethrough.

The first few seconds during which the heat of the exhaust gases passing through 2 is applied to 13, will cause the temperature of the air in 13 to rise quickly to about 400 'F. and the temperature therein remains approximately stationary thereafter as long as the 7 engine is idling, but an increase in engine speedcauses a higher temperature to be transmitted from the exhaust gases to 13. This higher temperature applied to 13 causes increased expansion' of air in 13 and thereby causes a further movement in 9. whereby 22 is further revolved and the supply of gasoline through 29 is further reduced by the admission of more air through port 31. Ultimately suflicient temperature applied to 13, depending on the cubic contents thereof. may cause 30 to be completely closed, so that no further gasoline may be drawn therethrough. While this method is entirely. operative. I. prefer to get a better regulation on the pressure applied to 9 through 14 by having an additional bulb 13 inserted in the water jacket 18 and connected to 14 by 14. for the reason that while the exhaust temperature applied to 13' causes a rapid rise to about 400 in 13, thereby giving an initial quick movement' to 22, the temperature of the cooling water in 18 rises more slowly so that the temture oi the cooling water in 18.

perature applied to the second bulb 13 in 18 is relatively slow, the controlling factor being truly the temperature of the cooling Water in jacket 18. The combination of the two, owing to differences in the bulb size of 13 and 13, gives an initial quick movement to 22, thereby cutting down the overly rich mixture supplied therethrough and thereafter the richness of the mixture is gradually decreased in proportion as the temperature of the engine rises, as indicated by the tempera- The control of the valve 22 by the bulb 13 insures a proper mixture in starting'the engine while it is in a heated condition. In cool weather the bulb 13 will soon becomecold after the engine stops running, and if it were notfor the bulb 13, which is controlled by the heat of the engine, the mixture would be too rich for starting the motor while it is still hot.

At extremely cold temperature, resistance coil 34 may be heated, in order to vaporize part of the gasoline supplied through 22 and thereby avoid possible dilution of crankcase Oil and cut down the time of supplying an overly rich mixture for the initial start. The vacuum for operating the vacuum tank 6 is applied from 7 through 15, but this is merely for convenience and pipe 15 may be direct connected to manifold 3 and it is obvious that the double diaphragm 9 shown in Fig. 3 may be substituted for the Bourdon tube 9 shown in Fig. 6 for operating spur gear 12.

Referring to Figs. 7 to 10 inclusive, the operation of my thermostatic control 18 shown applied to a carburetor, whereby the same results are achieved, but this modification may include the function of priming an engine and thereafter providing an idlingmixture through the same mechanism.

Bulb 13 is inserted in water jacket 18 and is joined by pipes 1e and 14 to 9 for operating 12. 12 is joined to valve 36, which is pivoted on the closed end ofthe bottom of 37, which is placed below the normal liquid. level in the float chamber 37 of carburetor l.

When the water jacket 18 is cold, port 39 in valve 36 will be wide. open With'respect to port 38 in 37 in Fig. 10 thereby permitting liquid fuel to stand in 36 to the height ofthe normal liquid level in 37*, 8 being closed air tight by cover 44, vacuum applied througln 40, 41 and d2 to the interior of 36 is also applied through :0 and 45 to the interior of 8 with the result that on cranking the engine to which 3 is attached, throttle 5 being substantially closed, the high vacuum supplied through 40 first causes a Very rich mixture to be drawn through 36, by removing the gasoline standing therein, and at the same time the vacuum applied through to the interior of 8 causes a. quick movement of Bourdon tube 9, irrespective of the temperature In ,soi.

zle 53. A. light spring fiil 18, thus causing the rotation of 36 a predetermined amount and cutting down the supply of gasoline through 38 by a partial closing of 39 and at the same time reducing the suc tion on 42 by the admission of more air through 41.

Thereafter, the overly rich mixture ha ring caused the initial tiring charges for the eu giue, the increased temperature of 18 will cause a further rotation of 36 due to the expansion of air in bulb 13, as already doscribed,but in the present instance the amount of air passing through 41 and the amount of gasoline passing through 39 are so arranged I device may be applied to the main gasoline feeding jets of the carburetor for all speeds of the engine including idling. It is also ob vious that the connections made with 14 as shown in Fig. & may be substituted to give the same effect as 4-5, shown in Fig. '2', the object being in both cases the supply of an overly rich mixture for a few seconds, then the cutting down to a rich mixture, and finally running the engine on a normal mixture when its temperature reaches the proper condition.

In Figs. 5 and 'i', the pipe 7 is shown as con nected to vacuum tank 6, but this is merely shown as a convenience, the same result being obtained by opening 41 direct to atmosphere and connecting 7 to another part of mani told 3. v

A modification is shown in Figs. 1 to 3 inclusive. in this modification all of the same results as described are obtained in a different manner, wherein 13 is shown as being placed in 2, but the end Boarder. tube 9 serves as a contact maker with an electrode' lti, set in insulation in 8, and connected thereto is a Wire a? leading to a solencid'e tt placed in a fitting 4:9 which is connected through 7 and 15 to the intake 3. q

A. fuel supply pipe 24edips below the liquid level fir-A in reservoir 20, 49 and 24: being threaded on to a nipple 50 through which a hollow valve 51 is adapted to slide having its upper part con'iprising a. disc 52 and a nozmay serve to help break 52 from its scat. v The lower part of 5l-is arranged to be always below the liquid level A--A and contains an air vent hole 5% arranged to-be below and above the liquid level AA upon the movement of 51 responsive to the action of solenoid 48., A gasket 55 is arranged between 52 and 48 in order to make an air tight seat between 52 and as.

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In place of the Bourdon tube 9, a double diaphragm 9 may be arranged for the same purpose and is an equivalent thereof;

The operation of this modification is as follows v hen engine 1 is cold, disc 52 is at the bot-. tom of fitting 49 and the current is broken by 46 being apart from the end of 9, whereby the current cannot be groundedf The lower end of 51 therefore a certain distance below the-liquid level o'f'AA. Upon starting engine 1 a solid stream of gasoline is drawn through 51 and 53 into 3 through 7 whereby an .overly rich mixture causes the engine to fire. The exhaust gases act quickly on 13 whereby the end of 9 causes a circuit to be made by touching' lti, Whereon solenoid 48 causes 51 tojump and seat itself on the bottom of 48, an air tight joint being made there by means of gasket 55.

The sudden upward jump of 51 causes air hole 54, which has reviously been submerged in the gasoline, to e open to atmosphere admitted to 20 through 21, thereby reducing the amount of gasoline drawn through 51 to a rich mixture and at the same time withdraws the vapors of light fractions from 20 and passes them to the engine. I Thereafter, the reduction of the level A-A, caused by the consumption of fuel through carburetor 4, uncovers a further air port 54 whereby the amount of gasoline fed through 51 is reduced suficient to idle the engine, or the pro ortion may be co-ordinated with that supplied to carburetor 4 tofeed' a proportion of gasoline and air continuously through 51;

In any event the same results are obtained in a different manner as already described, by first providing an overly rich mixture for starting the engine, then reducing the same quickly to a rich mixture andfinally reducing, the mixture to thatrequired for the normal operation of the engine."

- While the volume of 13-is'normally greater than 13*, the same may be varied to meet the requirements of any particular speed of action and the areas of and 40" may also be varied to the same end, but in general it will be seen that my invention is capable, through a wide range of modifications, of automatically feeding an overly rich mixtlire to an 1 engine by its suction'from a liquid reservoir,

then quickly cutting the same down to a rich mixture and finally reducing the mixture to normal for the correct operation of the engine, or cutting the mixture off entirely, the

whole being responsive to heat transmitting elements of the engine itself.

Further, the elements comprising my apparatus are capable of automatic response to temperature, whereby the different proportions of mixture'are continued for greater ,or

less periods of time, the same being particularly illustratedby the comparative expanmeans,

sion or contraction of the tube 9, or its equivalents, by heat or cold.

Further, it is to'be noted that pipe 24 forms a bafile which prevents liquid fuel from splashing on the end of pipe 51 and the an -is admitted to the interior of 24 from 21' through 20 and holes 56 and 57 which may be placed at varying levels above A-'- Further, it is to be noted that pipe 24 forms a baffle which prevents liquid. fuel from splashing on the end of'pipe 51 and the air is admitted to the interior of pipe 24 from the vent 21 through the reservoir 20 and holes 56 and 57 which may be placed atvarying levels above AA. i

I claim L The combination with an internalcom bustion engine having an exhaust pipe and an intake manifold for air and fuel of a reservoir for liquid fuel, means to supply liq.- uid fuel from the reservoir to the intakemanifold at a point posterior to the throttle, and means actuated from the exhaust pipe and controlled by the heat of the exhaust in said pipe for governing the ratio of liquid fuel to air assing through the intake manifold.

2. T e combination with an internal'combustion engine having an exhaust. pi e and anintake manifold for air and fuel 0' a reservoir for liquid fuel, valve means for supplying liquid fuel from the reservoir to the intake manifold at a point posterior to the throttle, and means fastened to the exhaust pipe and controlled by the heat of the exhaust in said pipe for actuating said valve whereby the ratio of liquid fuel to air passing through the manifold may be varied.

3. The combination with an internal com-- bustion engine having an exhaust pipe and an intake manifold for air and fuel of a reservoir for liquid fuel, apassage for liquid fuel from the reservoir to' the intake manifold,

a valve in said passage, and means connected with the exhaust pipe for operating said valve so that air alone will pass through the same.

4. The combination with an internal combustion engine having an exhaust pipe and an intake manifold'for air and fuel of a reservoir for liquid fuel, a passage for liquid] fuel from the reservoir to the intake manifold and means connected with'the exhaust pipe and affected by the heat of the exhaust therein for opening and closing said'p'assage, whereby a ecreasing or increasing amount of liquid fuel is automatically supplied to the engine through said passage.

5. The combination with an internal combustion engine havin and exhaust ipe, an intake manifold for el and air an a fluid cooling system of a reservoir for liquidfuel, meansto supply liquid fuel from the reservoir to the intake manifold and means con-' nected with both the exhaust pipe and the the amount of cooling system for governing the ratio of, fuel "to air passing through the intake manifold.

G..In an internal combustion engine, an intake manifold, a carburetor for supplying an explosive mixture to said manifold, D'lOChitIllSID' for supplying an explosive mixture to said manifold independently of said carburetor, and means for automatically" controlling the amount of fuel flowing through said mechanism Without decreasing. air flowing therethroughh 7. In,combination, with an internal com-f bustion engine having an exhaust passage and an intake manifold, a reservoir for throttle in said passage, areservoir, a condu t connectmg said reservoir with said manifold on starting said engine, and means operated by the combined suction and temperature of said engine for suddenlyintroducing air along with said fuel on the start-' liquid fuel, a passage for conducting air; and ing of said engine and then radually reducliquid fuel from said reservoir, to said mani fold,a valve in said, passage, and means for automatically operating said valve for supplying a decreasing amount of fuel and an increasing amount of air to said manifold. through said passage as said engine warms up. w

.8. In combination with an internal com; bustion engine havin an intake manifold, a'reservoir for liquid fuel, a passage connectsaid manifold whereby the suction of the engine will create a par;

.tial vacuum in said passage to cause the transfer of fuel therethrough from said res- .ervoir to said manifold, and means for automatically breaking the vacuum in said. passage when said engine reaches a predetermined temperature.

9. In a fuel-feeding system, aninternal 1 combustion engine having anintake manifold, acarburetor forsupply'ing an explosive mixture to said manifold, means for supplying a charge of liquid fuel to said manifold on starting said engine, and'suction operated means for immediately reducing the richness of succeeding charges on the starting of said engine. I v

10;.In a fuel feeding system, aninternal combustion engine having an intake manifold, a'carburetor for supplying an explosive mixture tosaid manifold, means for supplying" liquid fuel to said manifoldindependently of said carburetor, and-meansoperated by thesuction of said engine for opening an air port immediately on' for introducing air withsaid liquid fuel.

3 11. In combination, an internal com ustion engineflhaving an intake passage and'a 'mally the engine for delivering a ternal combustion engine supplyingan overly rich mixture to the en rting said engine, ,Los' I 'dayof Mare A. D. 1923'.

ing to a normal mixture.

13. In a'fuel feeding system, an internal combustion engine having an intake manifold, means for supplying fuel to said manivalve device therein,

olding said valve in liquid fuel to ing said engine for operating said valve to reduce the rlchness of the mixture, and thercontrolled means for further reducing the richness of the mixture as the engine warms up.

14. In a fuel feedingsystem, an internal combustion engine having an intake manifold, means for supplying liquid fuel to said manifold on starting the. engine while cold, means actuated by'the suction of the engine and the heat of the exhaust forireducing the richness of' the mixture ,upon starting the engine, and means-controlledby the heat of thin mixture to said manifold on starting said engine while in heated condition.

comparatively 1 I 15. A method of supplyingfuel'toan in-' v ch consists in gine at cranking speeds upon starting it while cold, suddenly reducing it' to a rich mixture when the engine fires, and then gradually reducing the richness of the mixture to norm'al as the engine reaches its normaloperatingtemperature.

Si ed at Wilmington; in the courlty of geles and State of California, this 13 CHARLES LAWRENCE STOKES, 

